Question: Nadia had to read papers 24 through 43 for homework last week. If Nadia read all of the papers she was assigned, how many papers did she read?
Answer: Instead of counting papers 24 through 43, we can subtract 23 from each number so we instead consider papers 1 through 20. We see that Nadia read 20 papers. Notice that she read 20 and not 19 papers.